ABSTRACT

Bi₄BaTi₄O₁₅(BBTO), an Aurivillius oxide, which is a mixed metal bismuth–layered based oxide fabricated by chemical route, has shown highly efficient photocatalytic activity in degradation of organic dye besides possessing high dielectric constant. The obtained material was characterised by various techniques like Fourier Transform Infrared (FTIR), transmission electron microscope, Scanning Electron Microscopy-Energy Dispersive X-rays Spectroscopy (SEM-EDX) X-ray powder diffraction (XRD), Zetasizer Nano-ZS, Ultraviolet- differential reflectance spectroscopy (UV-DRS), Brunauer–Emmett–Teller, Atomic Force Microscopy (AFM) and X-ray photoelectron spectra for the phase identification, microstructural analysis, bandgap determination, elemental analysis and oxidation state of the material. XRD data confirm the presence of single-phase BBTO ceramic, corroborated by Le-Bail fitting analysis. A high dielectric constant value of 3.08 × 10³ was obtained for the BBTO ceramic at 368 K. The material is stable in suspension form in solution and is a highly efficient photocatalyst. BBTO degraded 80% of RhB dye within 1 h of time period under UV light via major reactive species OH^. radicals and O₂^.- , generated during the photocatalytic reaction, which is proved to be following the first-order kinetics.

摘要

Bi ₄ BaTi ₄ O ₁₅（BBTO）是一种Aurivillius氧化物，是一种通过化学途径制备的混合金属铋层状氧化物，除了具有高介电常数外，在降解有机染料方面表现出高效的光催化活性。所获得的材料通过各种技术如傅里叶变换红外 (FTIR)、透射电子显微镜、扫描电子显微镜-能量色散 X 射线光谱 (SEM-EDX) X 射线粉末衍射 (XRD)、Zetasizer Nano-ZS、紫外- 微分反射光谱 (UV-DRS)、Brunauer-Emmett-Teller、原子力显微镜 (AFM) 和 X 射线光电子光谱，用于材料的相鉴定、微观结构分析、带隙测定、元素分析和氧化状态。XRD 数据证实存在单相 BBTO 陶瓷，由 Le-Bail 拟合分析证实。3.08 × 10 的高介电常数值^BBTO陶瓷在 368 K 时获得了 3。该材料在溶液中以悬浮形式稳定，是一种高效的光催化剂。BBTO 在紫外光下通过主要活性物质 OH 在 1 小时内降解 80% 的 RhB 染料^。光催化反应过程中产生的自由基和O ₂ ^.-，证明其遵循一级动力学。